With earlier Phantoms DJI never recommended doing IMU calibration unless necessary.
But lots of people like to feel they are doing something so forum chat started spreading the idea of (completely unnecessary) IMU recalibrations out of the box and after firmware updates as well as compass recalibration after updates.
A word serach of the
P4P manual brings up no mention of recalibrating the IMU before flight.
If it was important, it should be there.
Reading over on RCgroups, here's something suggesting that completely unnecessary IMU calibrations are causing this problem.
RC Groups - View Single Post - Official Phantom 4 PRO ***Owner's Thread***
(Dr Turbo is one of DJI's top engineers)
I've never recalibrated a Phantom IMU out of the box or after updates and never had any problems.
When my
P4P shows up soon, I won't be trying to calibrate the IMU.